Converting from word to pdf, some e-mail links aren't clickable

Ok, I'm really stumped on this one. I've got a Word doc created with Word XP (aka Word 2002) The document is 186 pages long. It is a company directory and it has phone numbers and e-mail addresses of all the important people in the company. The user says suddenly some of the e-mail addresses in the PDF are no longer clickable, but some are. I've checked the properties of the hyperlink and the unclickable ones are the same as the clickable ones. We're converting them by clicking on the PDF icon on the Word tool bar (we're using Acrobat 5.0.5 which is our company standard for creating PDFs) When the file is saved, you can open it up in Acrobat (we use Reader 6.0.1) Some of the e-mail links work. You just click on the underlined e-mail address in the PDF and then outlook pops up. Some of the other links which look the same (blue and underlined), you click on them and nothing happens. If you go back into the word doc and click the link, it works fine. I just freshly imaged a Optiplex D620 with Office XP and Acrobat 5.0.5 and the same thing happens. So I'm stumped on why some links get converted and some don't. I'd love to post 1 page of the document that is having the problem, but everything in it is confidential :(